External stabilizing structure for work boots

ABSTRACT

The external stabilizing structure is a structural element for use in work boots and similar types of footwear. The external stabilizing structure comprises a molded footbed of firm yet flexible material that provides external support under both the heel and arch of the wearer&#39;s foot.

BACKGROUND OF THE INVENTION

1. Field of Invention

This invention relates to a permanent external stabilizing element for work boots.

2. Discussion of Relevant Prior Art

A person working in construction or a similar field often spends extended periods of time standing or walking on surfaces that do not evenly or fully support the person's boot or shoe. This uneven support may translate into foot discomfort and fatigue. For example, while standing on the rung of a ladder briefly may not result in discomfort or fatigue, a few hours of standing on the rung of a ladder will likely result in extreme discomfort for the person due to localizing of pressure points on a small portion of the foot. A worker is forced to either endure the discomfort or continually shift position in an attempt to change the pressure points. As a result, the worker is less focused on the job at hand and less efficient.

One common answer to this problem is to provide a leather tuck board between the insole and the outsole or midsole (if present) of the work boot. However, this results in an unnecessarily heavy and stiff boot. Such a design makes walking in the boot difficult and more strenuous. Thus, while the tuck board addresses the problem when the wearer is standing, the tuck board impedes the wearer's ability to walk comfortably and easily while wearing such boots.

Some examples of external heel counters are found in athletic shoes which are designed to completely replace an internal shoe counter. For example, an existing design for an athletic shoe includes an external heel counter made of a resilient material for greater stability and comfort which is intended to completely replace an internal shoe counter and is confined to the heel area. Since this is an athletic shoe application and immediate energy rebound is desired, the material chosen is aimed at resiliency and energy return and not durability and toughness. Such materials would break down quickly and offer little resistance to damage in a working environment. As a result, these designs are ill-suited for work boots.

Another existing design reveals the use of a multi-layered sole on a hiking boot. The hiking boot has a reinforced element of semi-stiff plastic that forms one layer extending beneath the entire user's foot. It has two external stabilizing strips or arms that extend back to protect and support the heel. The heel portion of the layer does not connect with the stabilizing strips or arms. The heel is not fully connected to the reinforcement under the portion heel, but instead is only connected to the arch portion. Since this design is used in a hiking boot, it is aimed at adding stability while walking and allowing better return energy. As a result, these designs are also ill-suited for work boots.

OBJECTS AND SUMMARY OF THE INVENTION

It is an object of the invention to provide tough, durable, all-day support to a work boot.

It is also an object of the invention to provide support of the wearer's foot arch.

It is also an object of the invention to provide transverse rigidity to prevent or resist the transverse twisting of the foot between the heel and the ball of the foot.

It is also an object of the invention to provide counter rigidity for supporting the heel of the foot.

It is also an object of the invention to fulfill these objectives with a single structural element without adding unnecessary weight or significantly compromising flexibility of the work boot.

In response to the above identified objectives, the external stabilizing structure was developed.

The external stabilizing structure is a structural element for use in work boots and possibly other types of footwear. The external stabilizing structure comprises a molded footbed of stiff and resilient material that provides external support under the heel and arch of the wearer's foot. It also enhances the stability of the heel by enhancing the internal counter of the boot.

More specifically, the external stabilizing structure comprises a single piece of stiff and resilient hard-molded material that provides arch support, internal counter enhancement, increased transverse rigidity and counter rigidity to a work boot. The external stabilizing structure is permanently integrated between the upper and outsole or the midsole (if present) of a boot and is shaped to support the wearer's foot. An outsole of a boot is secured to the external stabilizing structure using an adhesive or cement or a stitched welt or a combination thereof. The external stabilizing structure is secured to the boot upper using adhesives and stitching.

By using a single piece of stiff and resilient hard-molded material, pressure points are defused throughout the length of the external stabilizing structure, thereby enhancing the wearer's comfort and stability while standing on ladder rungs, uneven or rocky surfaces and the like. But unlike a leather tuck board, the boot retains flexibility for comfortable walking and the weight of the external stabilizing structure is minimal, especially compared to a tuck board.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exterior side-view of the external stabilizing structure.

FIG. 2 a is a top-down view the external stabilizing structure.

FIG. 2 b is a front to back cross-sectional side-view of the external stabilizing structure.

FIG. 3 a is an exterior side-view of the external stabilizing structure with the arch support.

FIG. 3 b is a bottom-up view of the external stabilizing structure.

FIG. 4 a is a side to side cross-sectional view of the external stabilizing structure with the arch support.

FIG. 4 b is a side to side cross-sectional view of the external stabilizing structure.

FIG. 5 is a cross-sectional side to side view of the external stabilizing structure including the arch support.

FIG. 6 is an external view of the back or heel-end of the external stabilizing structure.

FIG. 7 is a view of a work boot including the external stabilizing structure.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to FIG. 1, the external boot stabilizing structure (10) is a structural element for use in work boots and similar types of footwear. More specifically, the external stabilizing structure (10) comprises a molded footbed (14) and a heel support structure (16). The external stabilizing structure (10) is designed to integrate into conventional work boot designs with little or no modification of the design. The external stabilizing structure (10) extends from the heel towards the toes of the wearer to provide external support to the upper under approximately 75% of the wearer's foot. It also enhances the stability of the heel by augmenting the internal counter of the boot upper. The external stabilizing structure (10) comprises a single piece of stiff and resilient hard-molded material, such as plastic, that is permanently secured to the bottom of the boot upper and above the boot outsole or midsole (if present).

The molded footbed (14) of the external stabilizing structure (10) has a top plane (22) and a bottom plane (24) and extends under the heel and arch of a wearer's foot. The molded material forming the external stabilizing structure may be molded plastic such as TPU (thermo plastic urethane), PU (polyurethane), PVC (polyvinylchloride), TPR (thermal plastic rubber), and ABS (acrylonitrile butadiene styrene), or rubber. In addition, combinations of materials, such as cork, rubber and laminates, may be used. The thickness and shape of the molded footbed (14) may vary to enhance the overall performance of the external stabilizing structure (10) both in terms of comfort and support.

The heel support structure (16) is an integral part of the external stabilizing structure (10). It provides exterior reinforcement to the internal counter of the boot upper. The heel support structure (16) is located behind and below the heel region of the boot upper and cups the entire heel of the wearer, providing additional rigidity and support beneath and behind the wearer's foot. The heel support structure (16) also protects the rear heel of the boot, which is prone to be damaged due to contact with hard and rough materials, operating machines, and other boots.

An optional, but preferred, welt deck extension (12) borders the bottom of the external stabilizing structure (10). The welt deck extension is where the outsole attaches to the boot outsole or midsole (if present). The boot outsole is the part of the completed boot that contacts the ground. If present, the boot midsole is located between the outsole and the external stabilizing structure (10) attached to the upper. The outsole is secured to the bottom of the external stabilizing structure (10) using either an adhesive or cement welt or a stitched welt, which is sewn through the welt deck extension (12), or a combination thereof. Stitched welts placed through the welt deck extension (12) are preferred for easier outsole replacement, which is an important feature for a work boot.

A re-enforcing strengthening channel (18) provides a border of thicker material along the top exposed edge of the external stabilizing structure (10). The re-enforcing strengthening channel (18) enhances the overall strength of the external stabilizing structure (10) and increases the durability of the external stabilizing structure (10). It also serves an aesthetic roll by blending with design elements often found on work boots. An optional name plate depression (20) may also be provided on the exterior surface of the heel support structure (16) if it is desirable to allow placement of the brand name of the manufacturer on the heel of the boot.

Referring now to FIG. 2 a, the top plane of the molded footbed (22) includes an under heel area (28), an arch support (26) and a behind heel area (30). The material of the external stabilizing structure (10) is shaped so as to reinforce the interior support of the boot, particularly by providing support for the arch of the foot with an arch support (26) and support for the heel of the foot with a heel cup formed by the under heel area (28) and the behind heel area (30). Furthermore, by connecting these areas into a single structure, pressure in one area is transferred to the whole external stabilizing structure (10) helping to prevent pressure points on the wearer's foot. In addition to preventing pressure points, the single structure allows better support for the wearer when the bottom of the boot is not equally supported by an uneven surface. For example, if the wearer stands on the rung of a ladder, it is likely that the rung would only support the area under the arch of the foot. In a standard work boot without the external stabilizing structure (10), the wearer's heel would receive little support. A common response to this need is for the work boot to utilize a leather tuck, but a leather tuck is heavy and impedes flexibility while walking.

Unlike a standard boot without the external stabilizing structure (10), a boot with the external stabilizing structure (10) better distributes uneven pressure created by an uneven surface across the molded footbed (14) and the heel support structure (16) to prevent discomfort or fatigue at any single point in the wearer's foot. Furthermore, the support provided to the heel is very comfortable because the external stabilizing structure (10) provides a one-piece molded heel cup that evenly supports the heel from the bottom and back. Without the external stabilizing structure (10) the wearer's foot muscles would need to act to counteract the uneven support. The external stabilizing structure (10), as a result, increases the wearer's comfort and decreases fatigue.

FIGS. 2 a and 2 b are aligned to show the relative positions of features of the external stabilizing structure (10) from a top-down view (FIG. 2 a) and a cross-sectional side view (FIG. 2 b). FIGS. 2 a and 2 b show the exterior of the heel support structure (16), the interior surface of which is shown at 30.

In a preferred embodiment, the external stabilizing structure (10) is attached beneath a boot upper by a combination of adhesive and stitching. Referring now to FIG. 3 a, the stitching thread or cord is used to stitch through an arch stitching groove (32) and a heel stitching groove (34) into the boot upper (not shown) to further strengthen the attachment created using adhesives between the external stabilizing structure (10) and the boot upper. The heel stitching groove (34) and the arch stitching groove (32) form depressed channels in the external stabilizing structure (10). The depressed grooves provide some protection for the stitching thread or cord from abrasion and wear. FIGS. 3 a and 3 b are aligned to show the relative positions of features of the external stabilizing structure (10) from an exterior side-view with the arch support (FIG. 3 a) and a bottom-up view (FIG. 3 b).

Referring now to FIGS. 4 a and 4 b, these figures depict side to side cross-sectional views of the external stabilizing structure (10). FIG. 4 a shows the arch support (26). FIG. 4 b shows the side to side cross-sectional view of the area between the heel and the arch support.

Referring now to FIG. 5, the figure shows a cross-sectional side to side view of the external stabilizing structure (10) including the arch support (26). The slope of the arch support (26) of the external stabilizing structure (10) is shown. The variable thickness of the molded footbed (14) follows the natural contours of the foot and increases comfort and support.

Referring now to FIG. 6, a view of the exterior of the back of the external stabilizing structure (10) is provided, which shows a clearer image of the optional welt deck extension (12), heel stitching groove (34), the heel support structure (16), the re-enforcing strengthening channel (18), and the optional name plate depression (20). The overall height of the heel support structure (16), including the re-enforcing strengthening channel (18) and the welt deck extension (12), is between 40 mm and 50 mm. This is the preferred height range for the heel support structure (16) because this range offers the best support to the heel without contacting the wearer's ankle or interfering with the movement of the wearer's ankle joint.

Referring now to FIG. 7, the external stabilizing structure (10) is shown integrated into a work boot (35). The external stabilizing structure (10) is secured beneath the upper (36) with adhesives and stitching. Stitching is placed through the heel stitching groove (34) and arch stitching groove (32). The external stabilizing structure (10) is secured to the top of the outsole (38) using adhesives, stitching through the optional welt deck extension (12), or a combination thereof.

While the external stabilizing structure (10) may be composed of any suitable stiff and resilient material, TPU (thermo plastic urethane) is preferred if the outsole is stitched to external stabilizing structure (10), but any material demonstrating the same or similar durability, flexibility and strength characteristics may be chosen. If the outsole is secured with adhesive cement, then the external stabilizing structure (10) is preferably formed from carbon fiber composite.

In manufacturing any particular external stabilizing structure for use in a shoe or boot, the dimensions will vary in proportion to standard shoe and boot sizing parameters. As referenced below, a “last” or rough model of the human foot is used to assist in manufacturing the external stabilizing structure. For example, the external stabilizing structure for use in a standard men's size 9 work boot will have a length between 170 mm to 180 mm. During construction of a work boot containing the external stabilizing structure, the molded footbed of the external stabilizing structure ends 5 mm short of the ball of the last on a standard men's size 9 work boot. This leaves the ball of the last unsupported by the external stabilizing structure and free to flex. Again, on a standard men's size 9 work boot, the beginning of the arch support is positioned 65 mm to 75 mm from the heel, the center of the arch support is positioned 105 mm to 120 mm from the heel, and the end of the arch support is positioned 160 mm to 175 mm from the heel. These dimensions and ranges are important because the external stabilizing structure channels energy to flex at the ball of the boot and not at the heel breast which is where boots and shoes without the support will tend to flex in addition to at the ball of the foot. In addition to the shoe or boot size, the final dimensions of any external stabilizing structure manufactured will vary due to other elements, such as insulation which would change the overall size of the boot.

In manufacturing any particular external stabilizing structure, the molded footbed of the external stabilizing structure is contoured, in part, based on the last used in designing the boot. As a result, the contour of the molded footbed will vary in order to address changes in the last that are the result of different heel heights. When constructing boots, the height of the heel determines the application of the boot. A standard work boot is built to have a ⅝ inch heel height. In contrast, a cowboy boot has a 2 inch heel to hold the boot in the stirrup and a logger boot has a 2½ inch heel to hold onto the spike when climbing trees. This heel height, in part, determines the shape of the bottom of the last. Therefore, the exact contour of the molded footbed varies depending, at least in part, on the function of the boot and the related heel height.

The external stabilizing structure (10) provides additional material to support the wearer's arch by enhancing the arch support present in the upper. However, the thickness of the material on the external stabilizing structure (10) varies in other areas as well. The varying thickness supports the natural contours of the human foot. The bone structure in the foot is not flat, but instead is shaped to naturally absorb the forces encountered when the foot impacts the ground. The external stabilizing structure (10) cradles the foot. By cradling the foot, the external stabilizing structure (10) supports, instead of cushions, the foot and ankle so they are positioned to naturally absorb the impact of a step.

In addition to the direct advantages of the external stabilizing structure (10), the external stabilizing structure (10) also offers manufacturing advantages. First, since the external stabilizing structure (10) is a single piece of molded plastic, it can be integrated into footwear much faster than placing support and protection in the arch support and heel area separately, saving labor costs. Second, it is faster and less costly to utilize the external stabilizing structure (10) than to utilize a leather tuck, which is commonly used to attempt to address some of the problems that the external stabilizing structure (10) solves. Finally, since the external stabilizing structure (10) can be integrated into most footwear without any or significant reworking of existing designs, it offers a less costly way to address support problems that may come up after a shoe or boot has already been designed and sold.

The foregoing descriptions and figures of the invention are explanatory and illustrative only, and various changes and details may be made within the scope of the appended claims without departing from the true spirit of the invention 

1. An external boot stabilizing structure comprising: a molded footbed providing an arch support and a heel cup, wherein the molded footbed is shaped to cradle the natural contours of the human foot; and a heel support structure, providing support and protection behind the heel; wherein the external stabilizing structure is a single piece of stiff and resilient material for placement beneath an upper and above an outsole of an assembled boot or shoe.
 2. The external boot stabilizing structure of claim 1, wherein the stiff and resilient material is a plastic.
 3. The external boot stabilizing structure of claim 1, wherein the molded footbed is under approximately 75% of the upper.
 4. The external boot stabilizing structure of claim 1, further comprising a welt deck extension.
 5. The external boot stabilizing structure of claim 4, further comprising a re-enforcing strengthening channel.
 6. The external boot stabilizing structure of claim 5, further comprising a heel stitching groove.
 7. The external boot stabilizing structure of claim 6, further comprising an arch stitching groove.
 8. The external boot stabilizing structure of claim 1, wherein the heel support structure does not exceed 50 mm in height.
 9. An external boot stabilizing structure providing: a molded footbed providing an arch support; and a heel support structure; wherein the external stabilizing structure is a single piece of stiff and resilient material for placement beneath an upper and above an outsole of an assembled boot or shoe.
 10. The external boot stabilizing structure of claim 9, wherein the molded footbed is under approximately 75% of the upper.
 11. The external boot stabilizing structure of claim 9, further comprising a welt deck extension.
 12. The external boot stabilizing structure of claim 11, further comprising a re-enforcing strengthening channel.
 13. The external boot stabilizing structure of claim 12, further comprising a heel stitching groove.
 14. The external boot stabilizing structure of claim 13, further comprising an arch stitching groove.
 15. The external boot stabilizing structure of claim 1, wherein the heel support structure does not exceed 50 mm in height.
 16. A work boot having an external boot stabilizing structure comprising: an outsole; an upper; and an external boot stabilizing structure located beneath the upper and above the outsole, wherein the external boot stabilizing structure is a single piece of material shaped to support the arch and beneath and behind the heel.
 17. The work boot of claim 16, wherein the heel support structure does not exceed 50 mm in height.
 18. The work boot of claim 16, wherein the external boot stabilizing structure is secured to the upper using adhesives and stitches placed through a heel stitching groove and an arch stitching groove.
 19. The work boot of claim 16, further comprising a welt deck extension.
 20. The work boot of claim 19, wherein the outsole is attached to the external boot stabilizing structure by stitches placed through the welt deck extension. 